Broadly, the present invention relates to multi-blend segmented smoking products having two or more zones or segments which are generally in a spaced longitudinal relationship within an elongated rod, the segments being composed of different types of tobacco or tobacco substitute material. More particularly, the invention relates to a method and apparatus for making such segmented smoking products.
The tobacco industry long has recognized the potential value of a product containing more than one tobacco blend or tobacco substitute composition in separate locations within the tobacco rod. Despite this recognition of the desirability of such a product, however, the tobacco industry, as well as its machinery supplies, have failed in devising a practical solution to the problem of high-speed manufacturing of a segmented product. The multi-blend segmented cigarette as used herein generally refers to a single-length cigarette having only a first blend located at one end of the cigarette and a combination of the first blend and a second blend at the other end.
The art is replete with ideas for products containing more than one tobacco blend or composition. For example, British Pat. No. 250,063, issued in 1926, proposes a cigarette having more than two segments composed of tobaccos of varying strength gradations. However, no suggestions are given concerning adaptation of this idea to cigarette manufacturing techniques. Not only different blends of tobacco, but also tobacco substitute compositions lend themselves to this concept.
U.S. Pat. No. 3,902,504 discloses an "engineered cigarette" wherein rods are manufactured containing varying quantities of tobacco and tobacco substitute. The rods are wrapped and cut into segments, and then segments are arranged in a preselected pattern and joined by an overwrap to produce a segmented cigarette. In contrast to the present state of the art in high-speed cigarette manufacturing, the complexities introduced in this process would be prohibitive, bearing in mind the necessity to produce a marketable product.
U.S. Pat. No. 3,759,267 discloses a cigarette having two portions, one of natural tobacco and the other of a different type of tobacco or tobacco substitute, arranged as adjoining wedges, which is similar though not the same as a product manufactured by the method and apparatus of the present invention. However, the method for manufacturing this cigarette which is disclosed in U.S. Pat. No. 3,880,171 illustrates the great difficulty in manufacturing a product of this type. The apparatus disclosed in the patent differs radically from conventional cigarette making equipment, requiring specialized trimming and cutting apparatus to remove portions of the first blend carried on a perforated conveying belt. Furthermore, this apparatus attempts to separate the tobacco rod into sections by a blow-off unit which removes tobacco between double-length sections with puffs of air. Such a method does not easily lend itself to operation at production speeds in the range of 4,000 cigarettes per minute.
The tobacco industry and its machine suppliers have attempted to solve the cognate problem of creating the so-called "dense end," an area of increased density at the end of a cigarette to prevent tobacco from falling out, in a number of ways containing various individual elements of the type used in the present invention. However, the method in which these brown elements are used in the present invention and their relationship to one another differs greatly from the "dense end" systems. For example, U.S. Pat. No. 3,146,780 discloses a device with a tobacco conveying belt which receives a blend of tobacco from a hopper feed and a metering device which desposits additional amounts of the same blend on the continuously moving belt in response to variation in the rod density. U.S. Pat. No. 3,795,249 illustrates an apparatus for adding a portion of the same blend to the conveyor tape at specified locations prior to depositing the majority of the blend and cutting the form rod so that the added portions are coincident with each end of a single cigarette. Each of these techniques uses only a single blend and does not produce a multi-blend segmented product having a single blend at at least one end and a multi-blend at the other.